To test the hypothesis that chronic intrauterine pulmonary hypertension (PHTN) compromises pulmonary artery (PA) smooth muscle cell (SMC) O2 sensing, fluorescence microscopy was used to study the effect of an acute increase in Po2 on the cytosolic Ca2+ concentration ([Ca2+]i) of chronically hypoxic subconfluent monolayers of PA SMC in primary culture. PA SMCs were derived from fetal lambs with ...

BACKGROUND Hydrogen peroxide (H2O2) and reactive oxygen species are implicated in inflammation, ischemia-reperfusion injury, and atherosclerosis. The role of ion channels has not been previously explored. METHODS AND RESULTS K+ currents and membrane potential were recorded in endothelial cells by voltage- and current-clamp techniques. H2O2 elicited both hyperpolarization and depolarization of...

Two polysaccharides, named KCA and KCW, were extracted from Kjellmaniella crassifolia using dilute hydrochloric acid and water, respectively. Composition analysis showed that these polysaccharides predominantly consisted of fucose, with galactose, mannose and glucuronic acid as minor components. After degradation and partial desulfation, electrospray ionization mass spectrometry (ESI-MS) was pe...

Cardiac contractile cells depend on calcium in order to function. Understanding the regulation of influx, efflux, and release from sarcoplasmic reticulum is essential. The focus this investigation address how a reduction functional Ca2+-activated K+ (KCa) channels, via mutational line, might impact heart rate larva when SER also modulated through Ca2+ loading stimulation. larval tube exposed si...

The dwindling and scarcity of fossil energy sources is the basis transition, where renewable resources are increasingly valued. purpose cogeneration system studied in this article to recover residual heat from gases coming out chimneys cement kilns, produce at same time electricity required for offices residential houses workers. Cement kilns reputed be energy-intensive, generating excessive lo...

The brain controls fertility through release of gonadotropin-releasing hormone (GnRH), but the mechanisms underlying action potential patterning and GnRH release are not understood. We investigated whether GnRH neurons exhibit afterdepolarizing potentials (ADPs) and whether these are modified by reproductive state. Whole-cell current-clamp recordings of GnRH neurons in brain slices from ovariec...

Cheranov, Sergey Y., and Jonathan H. Jaggar. TNFdilates cerebral arteries via NAD(P)H oxidase-dependent Ca spark activation. Am J Physiol Cell Physiol 290: C964–C971, 2006. First published November 2, 2005; doi:10.1152/ajpcell.00499.2005.—Expression of TNF, a pleiotropic cytokine, is elevated during stroke and cerebral ischemia. TNFregulates arterial diameter, although mechanisms mediating this...

The nitrogen-containing bisphosphonates used for management of the patients with osteoporosis were reported to influence the function of renal tubular cells. However, how nitrogen-containing bisphosphates exert any effects on ion currents remains controversial. The effects of ibandronate (Iban), a nitrogen-containing bisphosphonate, on ionic channels, including two types of Ca2+-activated K+ (K...

Dong, Hui, Anders Smith, Marjan Hovaida, and Jimmy Y. Chow. Role of Ca -activated K channels in duodenal mucosal ion transport and bicarbonate secretion. Am J Physiol Gastrointest Liver Physiol 291: G1120–G1128, 2006. First published June 8, 2006; doi:10.1152/ajpgi.00566.2005.—Stimulation of muscarinic receptors in the duodenal mucosa raises cytosolic free Ca concentration ([Ca ]cyt), thereby r...

We examined the functional role of large-conductance Ca2+-activated K+(KCa) channels in the hamster cremasteric microcirculation by intravital videomicroscopy and characterized the single-channel properties of these channels in inside-out patches of membrane from enzymatically isolated cremasteric arteriolar muscle cells. In second-order (39 ± 1 μm, n = 8) and third-order (19 ± 2 μm, n = 8) cre...